Hostname: page-component-77c89778f8-fv566 Total loading time: 0 Render date: 2024-07-21T07:38:03.375Z Has data issue: false hasContentIssue false

Effects of Spring Wheat Seed Size and Reduced Rates of Tralkoxydim on Wild Oat Control, Wheat Yield, and Economic Returns

Published online by Cambridge University Press:  20 January 2017

Qingwu Xue
Affiliation:
Montana State University, Northwestern Agricultural Research Center, Kalispell, MT 59901
Robert N. Stougaard*
Affiliation:
Montana State University, Northwestern Agricultural Research Center, Kalispell, MT 59901
*
Corresponding author's E-mail: rns@montana.edu

Abstract

Spring wheat competitive ability has recently been demonstrated to co-vary with seed size. The objective of this study was to determine if spring wheat seed size would influence the effects of variable tralkoxydim rates on wild oat control, wheat yield, and economic returns. The factorial treatment arrangement consisted of three spring wheat seed size classes and five tralkoxydim rates. Wild oat density, panicles, and biomass decreased as spring wheat seed size and tralkoxydim rate increased, with the combined effect being additive. Wild oat variables decreased in a log-logistic manner as tralkoxydim rate increased during both years. However, tralkoxydim was less effective in 2000 than 2002, as indicated by the higher dosage required to reduce the wild oat variables by 50% (greater I50 values). In contrast, the effect of large seeded wheat in suppressing wild oat was more consistently expressed, with wild oat variables decreasing linearly as seed size increased. Wheat yield and economic returns increased exponentially as tralkoxydim rate increased. At the same time, wheat yield and economic returns were greater for wheat plants derived from large seed compared to those derived from small seed. Averaged over all other factors, adjusted gross returns of 578, 657, and 703 $/ha were realized for the small, medium, and large seed size classes, respectively. The combined use of large seeded wheat plus tralkoxydim applications provided greater wild oat control than did either single tactic. The use of large seeded wheat had a stabilizing effect that increased the consistency and durability of the weed management system while simultaneously improving economic returns.

Type
Research Article
Copyright
Copyright © Weed Science Society of America 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Literature Cited

Barton, D. L., Thill, D. C., and Shafii, B. 1992. Integrated wild oat (Avena fatua) management affects spring barley (Hordeum vulgare) yield and economics. Weed Technol. 6:129135.CrossRefGoogle Scholar
Bussan, A. J., Boerboom, C. M., and Stoltenberg, D. E. 2000. Response of Setaria faberi demographic processes to herbicide rates. Weed Sci. 48:445453.CrossRefGoogle Scholar
Harker, K. N. and Blackshaw, R. E. 2003. Leaf extension rate may help determine when low wild oat herbicide rates will be effective. Weed Technol. 17:829835.Google Scholar
Holm, F. A., Kirkland, K. J., and Stevenson, F. C. 2000. Defining optimum rates and timing for wild oat control in spring wheat (Triticum aestivum). Weed Technol. 14:167175.CrossRefGoogle Scholar
Kirkland, K. L. 1993. Weed management in spring barley (Hordeum vulgare) in the absence of herbicides. J. Sustainable Agric. 3:95104.CrossRefGoogle Scholar
Lindquist, J. L., Mortensen, D. A., Clay, S. A., Schmenk, R., Kells, J. J., Howatt, K., and Westra, P. 1996. Stability of corn (Zea mays)-velvetleaf (Abutilon theophrasti) interference relationships. Weed Sci. 44:309313.Google Scholar
O'Donovan, J. T., Harker, K. N., Blackshaw, R. E., and Stougaard, R. N. 2002. Effects of variable rates of imazamethabenz and difenzoquat on wild oat (Avena fatua) seed production, and wheat (Triticum aestivum) yield and profitability. Can. J. Plant Sci. 83:977985.CrossRefGoogle Scholar
O'Donovan, J. T., Harker, K. N., Blackshaw, R. E., and Stougaard, R. N. 2003. Effects of variable tralkoxydim rates on wild oat (Avena fatua) seed production, wheat (Triticum aestivum) yield, and economic return. Weed Technol. 17:149156.Google Scholar
O'Donovan, J. T., Harker, K. N., Clayton, G. W., and Hall, L. M. 2000. Wild oat (Avena fatua) interference in barley (Hordeum vulgare) is influenced by barley variety and seeding rate. Weed Technol. 14:624629.CrossRefGoogle Scholar
O'Donovan, J. T., Harker, K. N., Clayton, G. W., Robinson, D., Newman, J. C., and Hall, L. M. 2001. Barley seeding rate influences the effects of variable herbicide rates on wild oat (Avena fatua). Weed Sci. 49:746754.CrossRefGoogle Scholar
O'Donovan, J. T., Newman, J. C., Harker, K. N., Blackshaw, R. E., and McAndrew, D. W. 1999. Effect of barley plant density on wild oat interference, shoot biomass and seed yield under zero tillage. Can. J. Plant Sci. 79:655662.Google Scholar
[SAS] Statistical Analysis Systems Institute. 2000. SAS/STAT User's Guide. Version 8.1. Cary, NC: Statistical Analysis Systems Institute.Google Scholar
Seefeldt, S. S., Jensen, J. E., and Fuerst, E. P. 1995. Log-logistic analysis of herbicide dose–response relationships. Weed Technol. 9:218227.Google Scholar
Stevenson, F. C., Holm, F. A., and Kirkland, K. J. 2000. Optimizing wild oat (Avena fatua) control with ICIA 0604. Weed Technol. 14:608616.Google Scholar
Stougaard, R. N. 1999. Carrier volume adjustments improve imazamethabenz efficacy. Weed Technol. 13:227232.Google Scholar
Stougaard, R. N., Maxwell, B. D., and Harris, J. D. 1997. Influence of application timing on the efficacy of reduced rate postemergence herbicides for wild oat (Avena fatua) control in spring barley (Hordeum vulgare). Weed Technol. 11:283289.Google Scholar
Walker, S. R., Medd, R. W., Robinson, G. R., and Cullis, B. R. 2002. Improved management of Avena ludoviciana and Phalaris paradoxa with more densely sown wheat and less herbicide. Weed Res. 42:257270.CrossRefGoogle Scholar
Xue, Q. and Stougaard, R. N. 2002. Spring wheat seed size and seeding rate affect wild oat demographics. Weed Sci. 50:312320.CrossRefGoogle Scholar